This invention relates to plasticizers and more particularly to energetic plasticizers for plastic bonded explosives.
A number of new fluorinated binders [for example, perfluoroalkyl polyformals as described by H. G. Adolph and J. M. Goldwasser; U.S. Pat. No. 4,740,579 (1988) and U.S. Pat. No. 4,740,628 (1988)] have recently become available and energetic formulations that contain these new fluorinated binders along with nitro oxidizers/explosives (HMX, for example) have been prepared. These new highly fluorinated binders exhibit quite different chemical properties compared to the nitro oxidizers/explosives. Because of these differences in properties, the usual nitro plasticizers (FEFO, NG, TMETN) used in the formulations are attracted toward the nitro oxidizer/explosive and not the fluorinated binder. These differences in the attraction of the nitro plasticizer for the binder and oxidizer can cause the plasticizer to migrate during storage of the formulations. U.S. patent application Ser. No. 07/901,621, filed on Jun. 15, 1992 by Michael E. Sitzmann (identical to the current inventorship) discloses 2-polynitroalkyl-5-perfluoroalkyl-1,3,4-oxadiazole plasticizers which solve the migration problem.
It would be desirable to provide low melting plasticizers which do not migrate in fluoropolymer/nitroexplosive composites and which possess low melting points but which have lower volatilities but greater densities and energies than the 2-polynitroalkyl-5-perfluoroalkyl-1,3,4-oxadiazoles. Moreover, it would be desirable to provide plasticizers which possess the general properties (such as low melting points) of conventional fluoroplasticizers but which are less volatile and more dense and energetic than the conventional fluoroplasticizers.